Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only tell the agent this is a read-only, closed-world operation. The description adds substantial context beyond that: which tool families are gated by which chain list, that raw-RPC tools accept any rpc.ankr.com/<chain> slug across 200+ chains, and that each reply self-reports shaping via _meta.tier and _meta.tier_source. These behavioral traits are not recoverable from annotations or schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the core answer, then the per-family routing rules, then the escape hatch for raw-RPC, then the meta note — a sensible order with little waste. It is somewhat telegraphic and packs a lot into one block, which costs a little readability, but every sentence carries routing information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description must partly convey the return shape, and it does by naming the aapiChains/suiChains keys and the _meta.tier/_meta.tier_source reporting. It stops short of fully describing the reply structure (e.g. whether suiNote appears in the response body), leaving a small gap for an agent reasoning about the return value.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Zero parameters, so there is nothing for the description to disambiguate and the baseline applies. It correctly does not waste space restating an empty input schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description immediately defines the resource as which chains each tool family reaches, and then enumerates the families (aapiChains, suiChains, raw-RPC), which sharply separates it from all siblings — it is a routing/lookup tool, not a data fetcher. An agent can tell why it exists and when a sibling like getAccountBalance is the wrong pick without opening a schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives an explicit when: 'call this before one of them on an unfamiliar chain', naming the exact tool set (getAccountBalance, getWalletActivity, getNFTs, getTokenHolders, getTokenPrice, getTokenPriceHistory). It also states an exclusion — raw-RPC tools and rpcCall are not constrained by these lists — so both the use case and non-use case are covered.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.